Heat exchanger



June 7, 1966 ODDY 3,254,708

HEAT EXCHANGER Original Filed Aug. 14, 1956 2 Sheets-Sheet 2 5 g m A m e a q i l United States Patent 3,254,708 HEAT EXCHANGER Edward P. Oddy, Detroit, MlClL, assignor to Borg-Warner Corporation, a corporation of Illinois Continuation of application Ser. No. 603,950, Aug. 14,

1956. This application May 28, 1962, Ser. No. 198,041 2 Claims. (Cl. 165-153) tanks, the tubes being separated by portions having fins or louvers provided therein, the devices incorporating the present invention having particular suitability as automobile-or other vehicle-radiators.

One object of the present invention is theprovision of a new and improved heat exchanger comprising a plurality of tubes for the conduction of fluid integrally joined to each other and to fluid conduits at the opposite ends of the tubes which requires no soldered 0r brazed joints.

Another object is the provision of a device in accordance with the preceding object in which fins or louvers are provided which are formed from the material between the tubes and which are in intimate heat conducting relation with the fluid conducting tubes.

Another object is the provision of a device in accordance with the preceding objects in which the fins are formed by distorting slotted or pierced portions of the heat exchanger material separating adjacent tubes.

Another object of the present invention is the provision of a device in accordance with the preceding objects in which the cross sectional area of material of the portion joining each end of each fin to the remainder of the tube sheet is not substantially reduced in cross section below the cross sectional area of the material which exists in the fin proper. 1

Another object is the provision of a device in accordance with the preceding objects in which the thermal bond between the secondary and primary heat conducting surfaces is effected without separate bonding operations, the thermal conduction path comprising a portion of the heat exchanger itself.

Another object of the present invention is the provision of a device in accordance with the preceding objects in which the fins may be readily shaped to etlect a serpentine path of cooling fluid flow through the device.

Other objects and features of the invention will be readily apparent to those skilled in the art from the specification and appended drawings illustrating certain preferred embodiments in which:

FIGURE 1 is a front elevational view of a device constructed in accordance with the present invention;

FIGURE 2 is a sideelevational view of the device in FIGURE 1;

FIGURE 3 is a sectional view along the plane of line 3-3 of FIGURE 1;

FIGURE 4 is an enlarged sectional view along the plane of line 4-4 of FIGURE 1;

FIGURE 5 is an enlarged perspective view of a portion of the device illustrated in FIGURE 1;

FIGURE 6 is a view similar to FIGURE 3 illustrating a modification of the device illustrated in FIGURE 1;

FIGURE 7 is an enlarged sectional view along the plane of line 77 of FIGURE 5;

FIGURE 8 is a modification of the device illustrated in FIGURE I;

FIGURE 9 is an enlarged sectional view along the plane of line 9-9 of FIGURE 8.

With reference to the figures, which are more or less schematic, and with particular reference to FIGURE 1 .Modern Metals.

3,254,708 Patented June 7, 1966 there is disclosed therein means defining an integral fluid circuit which comprises a tube sheet 1 of aluminum or other suitable heat conducting and fluid impervious material. Such tube sheets may be either of the type manufactured by Reynolds Metal Co. or others known as material manufactured by the Roll-Bond process; or other similar constructions. The product marketed by Reynolds Metal Co., manufactured under the Roll-Bond process is described in the February 1956 issue of the magazine Modern Metals and also in the November 1954 issue of In using the term tube sheet herein reference is made to such types of structure or any other comparable or similar structure, which comprises an integral combination of tubing and tube spacing sheet formed from a plurality of sheets of metal integrally bonded together except in areas forming the fluid circuit. The tube sheet 1 comprises integrally an upper fluid carrying tank portion 2 and a plurality of spaced tubes 3 in fluid communication at one end with the tank portion 2. The tubes 3 are initially separated by relatively flat, thin, non-fluid carrying portions 4 integral with the tubes 3, In fluid communication with the opposite ends of each of the tubes 3 is a lower, fluid carrying tank portion 5 also integrally formed as part of tube sheet 1. The upper tank portion 2 may be connected by a suitable fluid tight bond, such as soldering, to a manifold 6; the lower tank 5 may be similarly connected to a lower manifold 7.

It should be noted, therefore, that the elements 2 As illustrated in FIGURE 5, each of the tubes 3 is' formed to be relatively thin laterally in the plane of the tube sheet andrelatively deep in a direction transverse the original plane of the tube sheet so that the major dimension (in a direction transverse the plane of the tube sheet) of each tube is several times its lateral dimension; this permits the fins 8 to have, as illustrated in FIGURE 5, a relatively substantial major dimension as compared with the minor dimension thereof.

As previously described, the flat areas 4 between the tubes 3 are integral with the tubes 3. As best illustrated in FIGURE. 7, when the fiat portions 4 are sheared or slitted, as previously explained, and the fins 8 are twisted out of the plane of portions 4 openings are formed in portions 4 of area'substantially equal to the area of the'fins to permit the flow of air or other fluid in a direction perpendicular to the plane of the tube sheet 1. The resultant connection between each medial side of each fin 8 and the adjacent portion of the flat area 4 is substantially in the form illustrated in the en-' larged view of FIGURE 7. In this figure, the sheared portion is represented by the length indicated as a; as the fins 8 are twisted there is a tendency for the material to tear partly within the area b; at the same time, the material in this area is slightly distorted as illustrated. There remains a tie of material between the fin 8 and the adjacent section of the flat portion 4 approximately of the section shown at c in FIGURE 7. It will be obvious to those skilled in the art that this section of material will transfer heat from the adjacent tube 3 and flat portion 4 to the fin 8.

It will be seen from the foregoing description that when the device is used, for example, as an automobile radiator fluid may pass from the vehicles engine to the upper manifold 6, or other comparable fitting, through the upper tank 2, the tubes 3, the lower tank 5 and into the lower manifold or other suitable fitting 7, from which it would be recirculated through the engine. This fluid will be cooled as it passes through tubes 3 by virtue of air flow along the surface of tubes 3-the primary cooling surfaces-and over the surfaces of fins S-secondary cooling surfaces. As illustrated in FIGURE 2, when the device of the present invention is utilized as an automobile radiator it is preferable to employ a plurality of axially spaced tube sheets 1 of the general type previously described. As illustrated in FIGURE 3, all of the fins 8 and tubes 3 may be axially aligned, or as illustrated in FIGURE 6 the tubes 3 and fins 8 may be staggered toproduce air turbulence as it flows through the radiator. It should also be noted, as also illustrated in FIGURE 2, that the fins in the plurality of axially spaced tube sheets may either be horizontal or may be at an angle to the horizontal to produce a serpentine air flow through the radiator. It will be obvious to those skilled in the art that the integral, intimate bond between the tubes 3 and fins 8 will effect a substantially improved degree of thermal conductivity therebetween which will make the device of the present invention a singularly efficient heat exchanger and one which is simply and readily produced.

Considering now the modification illustrated in FIG- URES 8 and 9, it should be understood that the particular modification illustrated therein is identical-with respect to the elements previously described with the exception of the formation of the fins and their attachment to the remainder of the strucure. In the embodiment illustrated in FIGURES 8 and 9, the thin portions 4 between the tubes 3 are initially provided with a plurality of vertically spaced, narrow, pierced slots, (shown in the upper part of FIGURE 8) the flat material between the slots then being twisted to form fins 8 which are angularly disposed with respect to portions 4 and preferably of the width from /s inch to inch (as shown in the lower part of FIGURE 8 and FIGURE 9). By forming the fins 8 in this manner there is no appreciable reduction in the cross section of material through which the heat must flow from the tube to the fins; in other words the area of the material joining each tube and the adjacent fin is substantially equal in cross section to the amount of cross section of material which exists in the fin 8' itself.

It will readily appear to those skilled in the art that the device of the present invention is a substantial improvement over heat exchangers previously known in that there are-with the exception of the connection of the tube sheets to the upper and lower manifolds-no soldered or brazed joints whatsoever so that the manufacturing process is significantly simplified and the possibility of leaks substantially eliminated. In addition, the necessity for effecting the proper bond between the secondary surfaces, comprising the fins, in radiators of the prior art is obviated and in the present invention there is no chance whatsoever of an improper bond or thermal contact between the fins and the tubes inasmuch as the connection between these elements is an integral one. Not only is this a significant factor from a manufacturing standpoint, but it ensures a desirable product throughout the length of utilization of the device inasmuch as the bond between the secondary and primary surfaces of the structure cannot be less than initially contemplated because of errors in the manufacturing process, vibration or aging. In addition, higher internal fluid pressures are possible than with any of the heat exchangers previously employed, so that the size of the heat exchanger itself may be significantly reduced with a consequent substantial saving in cost and weight.

As a specific example, for illustrative purposes only and not as a limitation, of the manner in which the tube 4- sheets described herein may be fabricated, the teachings of United States Letters Patent No. 2,690,002 issued Sept. 28, 1954 to Leland H. Grenell may be employed. This application is a continuation of an application led Aug. 14, 1956, Ser. No. 603,950 entitled Heat Exchanger, now abandoned.

While certain preferred embodiments of the invention have been specifically disclosed, it is understood that the invention is not limited thereto, as many variations will be readily apparent to those skilled in the art and the invention is to be given its broadest possible interpre tation within the terms of the following claims:

I claim:

1. A heat exchanger, comprising: a tube sheet having a plurality 'of tubes integrally formed therewith adapted to receive and conduct fluid therethrough, said tubes being spaced apart by non-fluid carrying web portions of said tube sheet means; and a plurality of substantially flat single ply fin means formed out of said non-fluid carrying web portions, said fin means defining edge portions and side port-ions, said side portions being integral with said tubes and being connected at a medial zone thereof to the adjacent Web portions of said tube sheet means by twisted portions so that said fin means are disposed angularly and out of the plane of said Web portions on both sides of said tube sheet means and extend in a direction transverse to the original plane of the tube sheet means, said fins being in heat conducting relation with said tubes through said web portions and said twisted portions so as to provide secondary heat exchange surface therefor; said fin means and said web portions defining openings substantially equal in area to the area of the fin means.

2. A radiator comprising a plurality of aligned tube sheets; each of said tube sheets being constructed and arranged to form a fluid circuit system comprising a plurality of tubes adapted to conduct fluid spaced apart by nonfluid carrying .portions of said tube sheet means integrally connected to said tubes, and substantially fiat fin means integral with and formed out of said last named portions of said tube sheet means projecting angularly out of the plane of said portions whereby openings are formed in said portions through which a heat conducting medium may pass and said fin means are at all times in heat conducting relation with said tubes to provide secondary heat exchanging surfaces therefor; fluid conducting means in fluid communication with each of said tube sheets; the angular relation between the fins of one tube sheet and the remainder of said one tube sheet being different from the angular relation between the fins of the adjacent tube sheet and the remainder of said adjacent tube sheet whereby the heat conducting medium flowing through the radiator is forced to follow a serpentine path.

References Cited by the Examiner UNITED STATES PATENTS 1,125,027 l/1915 Max-Kretschmer -130 1,737,251 11/ 1929 Kuenstler 165-130 1,969,439 8/1934 Wentworth et al. 165-152 2,097,851 11/1937 Wenzl 165-170 2,190,494 2/1940 Templin 29-1573 2,286,271 7/1942 Higham 165-183 2,471,960 5/1949 Johnson 165-67 2,585,912 2/1952 wBuschow et al. 165-140 2,703,226 3/1955 Simpelaar 165-179 2,759,247 8/1956 Grenell et al. 165-168 2,779,086 1/ 1957 Ruppel et al.

2,856,164 8/1958 Adams 165-170 3,104,701 9/1963 Jacoby 165-148 ROBERT A. OLEARY, Primary Examiner.

EDWARD J. MICHAEL, Examiner. T. W. STREULE, Assistant Examiner. 

1. A HEAT EXCHANGER, COMPRESING: A TUBE SHEET HAVING A PLURALITY OF TUBES INTEGRALLY FORMED THEREWITH ADAPTED TO RECEIVE AND CONDUCT FLUID THERETHROUGH, SAID TUBES BEING SPACED APART BY NON-FLUID CARRYING WEB PORTIONS OF SAID TUBE SHEET MEANS; AND A PLURALITY OF SUBSTANTIALLY FLAT SINGLE PLY FIN MEANS FORMED OUT OF SAID NON-FLUID CARRYING WEB PORTIONS, SAID FIN MEANS DEFINING EDGE PORTIONS AND SIDE PORTIONS, SAID SIDE PORTIONS BEING INTEGRAL WITH SAID TUBES AND BEING CONNECTED AT A MEDIAL ZONE THEREOF TO THE ADJACENT WEB PORTIONS OF SAID TUBE SHEET MEANS BY TWISTED PORTIONS SO THAT SAID FIN MEANS ARE DIS- 